Display device and touch detection device

ABSTRACT

A display device is provided and includes a plurality of drive electrodes; a mesh-patterned first shield electrode comprising a plurality of first openings and a first electrode portion located between the first openings adjacent to each other, an area of the first electrode portion being greater than an area of the first openings; and a first power line provided with a predetermined voltage, wherein the first openings and the first electrode portion overlap the first power line.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/678,326, filed on Nov. 8, 2019, which application is based upon andclaims the benefit of priority from Japanese Patent Application No.2018-210187, filed Nov. 8, 2018, the entire contents of which areincorporated herein by reference.

FIELD

Embodiments described herein relate generally to a display device and atouch detection device.

BACKGROUND

A display device comprising a sensor which detects contact or approachof an object has been developed. As an example of an electrostaticcapacitance type sensor, the following structure is known. That is, adrive electrode is provided in one of substrates which face each other,and a detection electrode is provided in the other substrate. A powerline for supplying a signal potential is electrically connected to thedrive electrode, and a wiring line for reading an output signal iselectrically connected to the detection electrode.

If the wiring line is capacitively coupled to, for example, the powerline, a capacitance value detected by a detection circuit fluctuates,and sensitivity of the sensor may be deteriorated. Therefore, in orderto suppress the capacitive coupling between the wiring line and thepower line, the sensor may comprise a shield electrode overlapping thepower line. Parasitic capacitance produced between the shield electrodeand the wiring line should preferably be as low as possible. On theother hand, if the area of the shield electrode is reduced for thepurpose of reducing the parasitic capacitance, electromagneticinterference (EMI) noise radiating from the power line cannot besufficiently blocked.

SUMMARY

The present disclosure relates generally to a display device and a touchdetection device.

According to one embodiment, a display device includes a first substrateincluding drive electrodes, a second substrate facing the firstsubstrate and including detection electrodes, and a mesh-patterned firstshield electrode arranged in a non-display region in the secondsubstrate. The first shield electrode has a first opening and anisland-shaped first electrode portion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view schematically showing a display device 1according to the first embodiment.

FIG. 2 is a sectional view showing a configuration example of a displayregion DA shown in FIG. 1.

FIG. 3 is a plan view showing a configuration example of a firstsubstrate SUB1 shown in FIG. 1.

FIG. 4 is an illustration schematically showing connecting portionswhich electrically connect a drive electrode Tx and switch circuits C1and C2.

FIG. 5 is a plan view showing a configuration example of a secondsubstrate SUB2 shown in FIG. 1.

FIG. 6 is a plan view schematically showing a configuration example of anon-display region NDA shown in FIG. 5.

FIG. 7 is an illustration schematically showing a sensor 4.

FIG. 8 is an illustration showing an equivalent circuit of FIG. 7.

FIG. 9 is an enlarged plan view of a region A1 shown in FIG. 6.

FIG. 10 is an enlarged plan view of a vicinity of a power line VP1 shownin FIG. 9.

FIG. 11 is an enlarged plan view of a part of a shield electrode SL1shown in FIG. 10.

FIG. 12 is an enlarged plan view of a region A2 shown in FIG. 6.

FIG. 13 is an enlarged plan view of a vicinity of a power line VP2 shownin FIG. 12.

FIG. 14 is an illustration for explaining the relationship between thearea of an opening OP1 and the shielding effect of the shield electrodeSL1, and the shape of an overcoat layer OC.

FIG. 15 is a plan view showing another example of the shield electrodeSL1.

FIG. 16 is a plan view showing another example of the shield electrodeSL1.

DETAILED DESCRIPTION

In general, according to one embodiment, a display device comprises afirst substrate comprising drive electrodes, a second substrate facingthe first substrate and comprising detection electrodes, and amesh-patterned first shield electrode arranged in a non-display regionin the second substrate. The first shield electrode comprises a firstopening and an island-shaped first electrode portion.

According to another embodiment, a touch detection device comprises afirst substrate comprising drive electrodes, a second substrate facingthe first substrate and comprising detection electrodes, and amesh-patterned first shield electrode arranged in a region in which thedetection electrodes are not arranged, in the second substrate. Thefirst shield electrode comprises a first opening and an island-shapedfirst electrode portion.

Embodiments will be described hereinafter with reference to theaccompanying drawings. Incidentally, the disclosure is merely anexample, and proper changes within the spirit of the invention, whichare easily conceivable by a skilled person, are included in the scope ofthe invention as a matter of course. In addition, in some cases, inorder to make the description clearer, the widths, thicknesses, shapes,etc., of the respective parts are schematically illustrated in thedrawings, compared to the actual modes. However, the schematicillustration is merely an example, and adds no restrictions to theinterpretation of the invention. Besides, in the specification anddrawings, the structural elements having functions, which are identicalor similar to the functions of the structural elements described inconnection with preceding drawings, are denoted by like referencenumerals, and an overlapping detailed description is omitted unlessotherwise necessary.

In the present embodiment, a liquid crystal display device having adetector is disclosed as an example of a display device. This liquidcrystal display device can be used for various devices such as asmartphone, a tablet computer, a mobile telephone, a personal computer,a television receiver, a vehicle-mounted device, and a game console. Asthe display device having the detector, other display devices such as aself-luminous display device comprising an organic electroluminescent(EL) element layer, a micro (μ) LED element or the like, and anelectronic paper type display device comprising an electrophoreticelement or the like can be applied.

FIG. 1 is a perspective view schematically showing a display device 1according to the first embodiment. A first direction X, a seconddirection Y and a third direction Z shown in the drawing are orthogonalto one another. Note that the first direction X, the second direction Yand the third direction Z may cross one another at an angle other than90 degrees. In the present specification, a direction toward thepointing end of an arrow indicating the third direction Z is referred toas above, and a direction toward the opposite side from the pointing endof the arrow is referred to as below. In addition, an observationposition at which the display device 1 is observed is assumed to belocated on the pointing end side of the arrow indicating the thirddirection Z, and a view in an X-Y plane defined by the first direction Xand the second direction Y from this observation position is called aplanar view.

The display device 1 comprises a display panel 2, an illumination unit3, a sensor 4, a control module 5, an IC chip 6, an IC chip 7, wiringsubstrates F1, F2 and F3, and the like.

The display panel 2 is, for example, a liquid crystal display panel. Thedisplay panel 2 comprises a first substrate SUB1, a second substrateSUB2, and a liquid crystal layer (not shown) which is held between thefirst substrate SUB1 and the second substrate SUB2. The first substrateSUB1 and the second substrate SUB2 face each other in the thirddirection Z. The display panel 2 has, for example, a rectangular shape.In the example illustrated, the display panel 2 has a substantiallyrectangular shape and has a pair of end portions EX1 and EX2 extendingin the first direction X and a pair of end portions EY1 and EY2extending in the second direction Y. However, the display panel 2 is notlimited to the example illustrated. Furthermore, the display panel 2comprises a mounting portion MT in which the first substrate SUB1extends farther than the second substrate SUB2. In the exampleillustrated, the mounting portion MT corresponds to a region of thefirst substrate SUB1 which extends farther in the second direction Ythan an end portion E2 of the second substrate SUB2. The end portion E2is located between a display region DA and the end portion EX1, andextends in the first direction X.

The display panel 2 comprises the display region DA in which an image isdisplayed, and a non-display region NDA which surrounds the displayregion DA. The display region DA is located within a region in which thefirst substrate SUB1 and the second substrate SUB2 overlap each other.In the example illustrated, the display region DA has a substantiallyrectangular shape and has a pair of long sides extending in the firstdirection X and a pair of short sides extending in the second directionY. However, the display region DA is not limited to the exampleillustrated. The display panel 2 is, for example, a transmissive typeliquid crystal display panel which displays an image by selectivelytransmitting light from the illumination unit 3. Note that the displaypanel 2 may be a reflective type display panel which displays an imageby selectively reflecting external light or the light from theillumination unit 3 or may be a transflective type display panel whichhas both the display function of the transmissive type display panel andthe display function of the reflective type display panel.

The illumination unit 3 is provided on the rear surface side of thedisplay panel 2, that is, directly below the first substrate SUB1. Theillumination unit 3 has substantially the same shape and substantiallythe same size as the display panel 2. The illumination unit 3illuminates the entire region of the display region DA. Although variousmodes can be applied to the illumination unit 3, the illumination unit 3comprises, for example, a light guide which faces the first substrateSUB1, and a light source such as a light-emitting diode (LED) which isprovided in an end portion of the light guide.

The sensor 4 is, for example, an electrostatic capacitance type sensor.The sensor 4 corresponds to a touch detection device which detects anobject contacting or approaching the display panel 2. The sensor 4comprises a plurality of detection electrodes Rx provided in the secondsubstrate SUB2.

The IC chip 6 is mounted on the mounting portion MT. The IC chip 6outputs various signals for displaying an image in the display regionDA. The IC chip 7 is provided in the control module 5. The IC chip 7outputs various signals for driving the sensor 4.

The wiring substrate F1 electrically connects the first substrate SUB1and the control module 5. The wiring substrate F2 electrically connectsthe second substrate SUB2 and the control module 5. The wiring substrateF3 electrically connects the illumination unit 3 and the control module5. The wiring substrates F1, F2 and F3 are, for example, flexible wiringsubstrates. The signals output from the IC chip 7 for driving the sensor4 are supplied to the display panel 2 via the wiring substrates F1 andF2.

FIG. 2 is a cross-sectional view showing a configuration example of thedisplay region DA shown in FIG. 1. The first substrate SUB1 comprises abasement 10, insulating layers 11, 12 and 13, signal lines S, a commonelectrode CE, pixel electrodes PE (PE1, PE2 and PE3), an alignment filmAL1 and the like. The basement 10 is formed of, for example, atransparent insulating material such as glass or resin. The insulatinglayer 11 is formed on the basement 10. The signal lines S are formed onthe insulating layer 11 and are covered with the insulating layer 12.The common electrode CE is formed on the insulating layer 12 and iscovered with the insulating layer 13. The pixel electrodes PE are formedon the insulating layer 13 and are covered with the alignment film AL1.Each pixel electrode PE is arranged in a region between the signal linesS which are adjacent to each other in the first direction X, and facesthe common electrode CE. In the example illustrated, each pixelelectrode PE has a slit ST. Each of the pixel electrode PE and thecommon electrode CE is formed of, for example, a transparent conductivematerial such as indium tin oxide (ITO) or indium zinc oxide (IZO).

The second substrate SUB2 comprises an overcoat layer OC, a basement 20,a light-shielding layer 21, a color filter layer 22, an overcoat(planarizing film) layer 23, an alignment film AL2 and the like, inaddition to the detection electrodes Rx. The basement 20 is formed of,for example, a transparent insulating material such as glass or resin.The basement 20 has a first surface 20A which faces the first substrateSUB1 and a second surface 20B which is located on the opposite side fromthe first surface 20A. The detection electrodes Rx are formed on thesecond surface 20B and are covered with the overcoat layer OC. Thelight-shielding layer 21 is provided on the first surface 20A. Thelight-shielding layer 21 faces each signal line S and delimits eachpixel PX. Here, the pixel PX corresponds to a minimum unit which can beindividually controlled in response to an image signal. The color filterlayer 22 covers the light-shielding layer 21 and is also in contact withthe basement 20. The color filter layer 22 includes a red color filterCF1, a green color filter CF2 and a blue color filter CF3. The colorfilters CF1, CF2 and CF3 face the pixel electrodes PE1, PE2 and PE3,respectively. The overcoat layer 23 covers the color filter layer 22.The alignment film AL2 covers the overcoat layer 23. Each of theovercoat layer 23 and the overcoat layer OC is formed of transparentresin.

The liquid crystal layer LC is sealed in between the alignment film AL1and the alignment film AL2. The alignment films AL1 and AL2 are, forexample, horizontal alignment films by which liquid crystal moleculesare aligned in a direction parallel to the main surfaces of thebasements 10 and 20. The orientations of the liquid crystal moleculesincluded in the liquid crystal layer LC are controlled by an electricfield formed between the common electrode CE and the pixel electrode PE.

In the present embodiment, the common electrode CE functions as anelectrode for driving the liquid crystal molecules and also functions asa drive electrode Tx provided in the sensor 4. That is, the commonelectrode CE controls the orientations of the liquid crystal moleculesin cooperation with the pixel electrode PE in a display period in whichan image is displayed in the display region DA. On the other hand, thecommon electrode CE functions as the drive electrode Tx which iscapacitively coupled to the detection electrode Rx in a sensing periodin which an object contacting or approaching the display region DA isdetected.

FIG. 3 is a plan view showing a configuration example of the firstsubstrate SUB1 shown in FIG. 1. The first substrate SUB1 comprises thedrive electrodes Tx and switch circuits C1 and C2. The drive electrodesTx are provided over almost the entire region of the display region DA.The drive electrodes Tx have, for example, a strip shape having asubstantially constant width. In the example illustrated, the driveelectrodes Tx extend in the first direction X, and are arranged in thesecond direction Y while being spaced a certain distance apart from oneanother in the second direction Y.

The switch circuits C1 and C2 are provided in the non-display region NDAand are electrically connected to the drive electrodes Tx. The switchcircuits C1 and C2 face each other across the drive electrodes Tx. Inthe example illustrated, the switch circuit C1 extends in the seconddirection Y in the vicinity of the end portion EY1. The switch circuitC2 extends in the second direction Y in the vicinity of the end portionEY2.

Control signals supplied from the IC chip 7 are supplied respectively tothe switch circuits C1 and C2 via the wiring substrate F1. In theexample illustrated, the IC chip 7 comprises a detection circuit RC. Thedetection circuit RC detects a sensor output signal which is output fromthe sensor 4. Note that the detection circuit RC may be provided in thecontrol module 5.

FIG. 4 is an illustration schematically showing connecting portionswhich electrically connect the drive electrode Tx and the switchcircuits C1 and C2 shown in FIG. 3. The switch circuit C1 includespotential supply lines VH1 and VL1 and a power line VP1. The potentialsupply lines VH1 and VL1 are wiring lines for supplying commonpotentials to the drive electrode Tx (common electrode CE) in thedisplay period. For example, a certain potential is supplied to thepotential supply line VH1, and a certain potential lower than that ofthe potential supply line VH1 is supplied to the potential supply lineVL1. The power line VP1 is a wiring line for supplying an AC potentialas a sensor drive signal to the drive electrode Tx in the sensingperiod.

The configuration of the switch circuit C2 is similar to that of theswitch circuit C1. That is, the switch circuit C2 includes potentialsupply lines VH2 and VL2 for supplying common potentials in the displayperiod, and a power line VP2 for supplying a sensor drive signal in thesensing period. The same potential as that of the potential supply lineVH1 is supplied to the potential supply line VH2, and the same lowpotential as that of the potential supply line VL1 is supplied to thepotential supply line VL2. The same AC potential as that of the powerline VP1 is supplied to the power line VP2.

The connections in the switch circuits C1 and C2 are switched insynchronization with each other such that the same potential will besupplied to the drive electrode Tx. This switching is controlled basedon control signals supplied from the IC chip 7. That is, in the displayperiod, the drive electrode Tx is electrically connected to thepotential supply lines VH1 and VH2 or the potential supply lines VL1 andVL2 based on the control signals supplied from the IC chip 7. In thesensing period, the drive electrode Tx is electrically connected to thepower lines VP1 and VP2 based on the control signals supplied from theIC chip 7.

FIG. 5 is a plan view showing a configuration example of the secondsubstrate SUB2 shown in FIG. 1. The second substrate SUB2 comprises thedetection electrodes Rx. The detection electrodes Rx are arranged overalmost the entire region of the display region DA. In the exampleillustrated, the detection electrodes Rx extend in the second directionY, and are arranged in the first direction X while being spaced acertain distance apart from one another in the first direction X.

The sensor output signals detected from the detection electrodes Rx inthe sensing period are transmitted to the IC chip 7 via the wiringsubstrate F2. In the sensing period, if an object which is a conductoror a dielectric (for example, a finger) contacts or approaches thedisplay region DA, a capacitance formed between the common electrode CEand the detection electrode Rx in the vicinity of the object changes.That is, the sensor output signal detected from the detection electrodeRx in the vicinity of the object exhibits a different value from thoseof the sensor output signals detected from the other detectionelectrodes Rx. The detection circuit RC detects that the object hascontacted or approached the display region DA based on the change of thesensor output signal detected from the detection electrode Rx. Inaddition, the detection circuit RC specifies a position in the displayregion DA where the object has contacted or approached.

FIG. 6 is a plan view schematically showing a configuration example ofthe non-display region NDA shown in FIG. 5. The second substrate SUB2comprises terminals TE1, wiring lines WL, shield electrodes SL1 and SL2and the like in the non-display region NDA.

The terminals TE1 are electrically connected to the wiring substrate F2shown in FIG. 5. The terminals TE1 are arranged in the first direction Xbetween the detection electrodes Rx and the end portion E2. In theexample illustrated, each terminal TE1 includes a first portion T11 anda second portion T12. The first portion T11 and the second portion T12are spaced apart from each other in the second direction Y. The firstportion T11 is closer to the display region DA than the second portionT12. The first portion T11 and the second portion T12 are electricallyconnected to the same detection electrode Rx by the wiring line WL.

The wiring lines WL are electrically connected to the detectionelectrodes Rx and are in a one-to-one correspondence with the detectionelectrodes Rx. In the example illustrated, the detection electrodes Rxare bent into a wave shape. For example, the wiring lines WL are drawnfrom both end portions of the detection electrodes Rx and are arrangedin the non-display region NDA. In the example illustrated, all thewiring lines WL are arranged on the end portion EY1 side of thenon-display region NDA. In other words, the wiring lines WL are notarranged in the non-display region NDA between the detection electrodesRx and the end portion EY2. More specifically, the wiring lines WL drawnfrom the detection electrodes Rx to the end portion EX2 side extendalong the end portion EX2, the end portion EY1 and the end portion E2,and are electrically connected to the second portions T12, respectively.The wiring lines WL drawn from the detection electrodes Rx to the endportion E2 side are electrically connected to the first portions T11,respectively.

Note that the arrangement of the wiring lines WL is not limited to theexample illustrated. For example, the wiring lines WL may be arranged onthe end portion EY2 side of the non-display region NDA. Alternatively,the wiring lines WL electrically connected to the detection electrodesRx arranged on the left side region in the drawing may be arranged onend portion EY1 side of the non-display region NDA, and the wiring linesWL electrically connected to the detection electrodes Rx arranged on theright side region in the drawing may be arranged on the end portion EY2side of the non-display region NDA.

The shield electrode SL1 is arranged between the wiring lines WL on theend portion EY1 side of the non-display region NDA. More specifically,the shield electrode SL1 extends along the end portion EY1, extendsalong the end portion E2 to the vicinity of the center of the secondsubstrate SUB2, and is electrically connected to the second portion T12.

The shield electrode SL2 surrounds all the detection electrodes Rx andthe shield electrode SL1. In the example illustrated, the shieldelectrode SL2 extends along the end portions E2, EY1, EX2 and EY2, andsurrounds the terminals TE1 except some terminals TE1 located on the endportion EY2 side. The shield electrode SL2 may be disconnected in partor may extend along two or three end portions of the end portions E2,EY1, EX2 and EY2. Alternatively, the shield electrode SL2 may bearranged in such a manner as to surround all the terminals TE1.

As indicated by a dash-dot-dot line in the drawing, each terminal TE2provided in the wiring substrate F2 overlaps both the first portion T11and the second portion T12. The terminal TE1 and the terminal TE2 areattached to each other by, for example, an anisotropic conductive filmor the like, and are electrically connected to each other. The sensoroutput signals output from the detection electrodes Rx are transmittedto the IC chip 7 shown in FIG. 1 via terminals T21 of the terminals TE2which are electrically connected to the detection electrodes Rx. Thepotentials applied to the shield electrodes SL1 and SL2 are suppliedfrom the IC chip 7 via terminals T22 of the terminals TE2.

The potential of each of the shield electrodes SL1 and SL2 is, forexample, the same potential as the potential (amplitude) of thedetection electrode Rx. Alternatively, the potential of each of theshield electrodes SL1 and SL2 is, for example, a fixed potential such asa ground potential. If the potential of each of the shield electrodesSL1 and SL2 is a fixed potential, the potential of each of the shieldelectrodes SL1 and SL2 may be supplied from a power line other than theIC chip 7.

Each of the detection electrode Rx, the wiring line WL, the terminal TE1and the shield electrodes SL1 and SL2 may be formed of a metal materialsuch as molybdenum, tungsten, titanium or aluminum and may have a singlelayer structure or a multilayer structure. Each of the wiring line WL,the terminal TE1 and the shield electrodes SL1 and SL2 is provided onthe second surface 20B of the basement 20 and can be formed of the samematerial as that of the detection electrode Rx. In the exampleillustrated, the overcoat layer OC is provided over the entire surfaceof the second substrate SUB2 except for the vicinity of the terminalsTE1. In the example illustrated, the overcoat layer OC is not providedin a substantially L-shaped region B which overlaps the wiring substrateF2. The overcoat layer OC covers all the detection electrodes Rx, thewiring lines WL and the shield electrodes SL1 and SL2. As a result,corrosion or the like of the detection electrodes Rx, the wiring linesWL and the shield electrodes SL1 and SL2 is suppressed.

FIG. 7 is an illustration schematically showing the sensor 4. Acapacitance C11 is formed between the detection electrode Rx and thedrive electrode Tx. If a finger contacts the display panel 2, capacitivecoupling occurs between the finger and the drive electrode Tx andbetween the finger and the detection electrode Rx. At this time, acapacitance C12 is formed between the finger and these drive electrodeTx and detection electrode Rx. Furthermore, if there is a potentialdifference between the wiring line WL and the other conductor locatedaround the wiring line WL, a parasitic capacitance C13 is producedbetween the wiring line WL and the other conductor. Here, the otherconductor corresponds to, for example, the shield electrodes SL1 and SL2and the like shown in FIG. 6.

FIG. 8 is an illustration showing an equivalent circuit of FIG. 7. Achange rate DI of the sensor output signal detected by the detectioncircuit RC is represented by irx/itx. Here, irx is a current flowingthrough the detection electrode Rx, and itx is a current flowing throughthe drive electrode Tx. If a finger contacts the display panel 2, due tothe capacitance C12, a current ifg of the current itx flows to thefinger side. Therefore, a change rate DI1 of the sensor output signal ina case where a finger is in contact with the display panel 2 isrepresented by the following formula.

DI1=(itx−ifg)/itx

Furthermore, if the parasitic capacitance C13 is produced between thewiring line WL and the other conductor, a current ip of the current itxflows to the parasitic capacitance C13 side. Therefore, a change rateDI2 of the sensor output signal in a case where a finger is in contactwith the display panel 2 and the parasitic capacitance C13 is producedis represented by the following formula.

DI2=(itx−ip−ifg)/(itx−ip)

From the above, DI2<DI1 is established. That is, if the parasiticcapacitance C13 is high, the change rate of the sensor output signal islow, and the detection sensitivity of the sensor 4 will be deteriorated.Therefore, it is necessary to reduce the capacitive coupling between thewiring line WL and the other wiring line as much as possible in thesensor 4.

FIG. 9 is an enlarged plan view of a region A1 shown in FIG. 6. Theregion A1 is a region including the end portion EX2 and the end portionEY1. As indicated by a dotted line, the power line VP1 provided in thefirst substrate SUB1 is located in the region A1 and extends in adirection in which the drive electrodes Tx are arranged, that is, in thesecond direction Y.

The wiring lines WL do not overlap the power line VP1. That is, in thenon-display region NDA in the vicinity of the end portion EY1, somewiring lines WLa of the wiring lines WL extending in the seconddirection Y are located between the power line VP1 and the displayregion DA in a planar view, and the other wiring lines WLb are locatedbetween the power line VP1 and the shield electrode SL2 in a planarview. Since the wiring lines WL do not overlap the power line VP1, theimpact of EMI noise radiating from the power line VP1 on the detectionelectrodes Rx can be reduced.

Each detection electrode Rx is formed of an aggregate of thin metalwires MW which are bent into a wave shape. The thin metal wires MWextend in substantially the second direction Y. In the exampleillustrated, each detection electrode Rx comprises a connecting portionP1 and electrode portions P2. The connecting portion P1 extends in thefirst direction X. The thin metal wires MW included in one detectionelectrode Rx are connected to the connecting portion P1. Some thin metalwires MW constitute the electrode portions P2. The detection electrodeRx comprises, for example, two electrode portions P2. In the exampleillustrated, each electrode portion P2 is formed of three thin metalwires MW. Although not shown in the drawing, in order to realizeuniformity of display in the display region DA, a thin metal wire at afloating potential may be provided between the electrode portions P2.

The shield electrode SL1 overlaps the power line VP1. The shieldelectrode SL1 extends in the second direction Y between the wiring linesWLa and the wiring lines WLb. Note that the shield electrode SL1 isspaced apart from the wiring lines WL. Since the power line VP1 to whichthe sensor drive signal is supplied is covered with the shield electrodeSL1 at, for example, the same potential as that of the detectionelectrode Rx, capacitive coupling between the power line VP1 and thewiring line WL which are at different potentials can be suppressed.Furthermore, in the present embodiment, the shield electrode SL1 has amesh pattern. Since the shield electrode SL1 has a mesh pattern, anoverlapping area in which the shield electrode SL1 and the power lineVP1 overlap is reduced. Therefore, even if the shield electrode SL1 andthe power line VP1 are at different potentials, capacitive couplingbetween the shield electrode SL1 and the power line VP1 can besuppressed, and the shield electrode SL1 can be easily driven with thesame amplitude as that of the detection electrode Rx. As a result, asdescribed with reference to FIG. 8, the decrease of the change rate ofthe sensor output signal output to the detection circuit RC can besuppressed, and the deterioration of the detection sensitivity of thesensor 4 can be suppressed.

The shield electrode SL2 is provided along the end portions EX2 and EY1in a region on the outside of the detection electrodes Rx. In addition,the shield electrode SL2 is provided in a substantially triangularregion in the vicinity of a corner portion CN in which the end portionEX2 and the end portion EY1 cross each other. More specifically, theshield electrode SL2 is arranged between the outermost wiring line WLand the end portion EX2 and between the outermost wiring line WL and theend portion EY1. For example, the shield electrode SL2 is spaced apartfrom both the end portion EX2 and the end portion EY1. In the exampleillustrated, a width WY1 of the shield electrode SL2 extending along theend portion EY1 is less than a width WX2 of the shield electrode SL2extending along the end portion EX2.

The shield electrode SL2 blocks, for example, electrostatic discharge(ESD) noise entering from the end portions EX2 and EY1 and the like andcoming toward the wiring lines WL. Therefore, entry of ESD noise to thesensor 4 is suppressed, and malfunction and breakdown of the sensor 4are suppressed. Furthermore, as is the case with the shield electrodeSL1, the shield electrode SL2 has a mesh pattern. Since the area of theshield electrode SL2 is reduced, even if the shield electrode SL2 andthe wiring line WL are at different potentials, capacitive couplingbetween the shield electrode SL2 and the wiring line WL can besuppressed. As a result, as described with reference to FIG. 8, thedecrease of the change rate of the sensor output signal output to thedetection circuit RC can be suppressed, and the deterioration of thedetection sensitivity of the sensor 4 can be suppressed.

In the example illustrated, the second substrate SUB2 comprises a shieldelectrode SL3 in addition to the shield electrodes SL1 and SL2. Theshield electrode SL3 is arranged between the wiring lines WLa and thedetection electrodes Rx. The potential of the shield electrode SL3 is,for example, the same potential as that of the detection electrode Rx.The shield electrode SL3 described above suppresses capacitive couplingbetween the wiring line WLa and the detection electrode Rx. Note thatthe potential of the shield electrode SL3 may be, for example, a fixedpotential such as a ground potential. In the example illustrated, theshield electrode SL3 is located in the display region DA, and as is thecase with the detection electrode Rx, the shield electrode SL3 is formedof wavy thin metal wires. Since the shape of the shield electrode SL3 issimilar to the shape of the detection electrode Rx, the detectionelectrode Rx and the shield electrode SL3 become less visible in thedisplay region DA.

FIG. 10 is an enlarged plan view of the vicinity of the power line VP1shown in FIG. 9. The shield electrode SL1 comprises openings OP1 andelectrode portions IE1. A part of the shield electrode SL1 overlaps thepower line VP1 in a planar view. That is, at least some of the openingsOP1, and some of the electrode portions IE1 overlap the power line VP1.In the present embodiment, the openings OP1 are regularly arranged. Inthe example illustrated, the openings OP1 are arranged in the firstdirection X and the second direction Y. In addition, the openings OP1are arranged in a staggered manner in directions in which thin wiresTW11 and TW12 which form the openings OP1 extend. The openings OP1 have,for example, a substantially square shape. Each electrode portion IE1corresponds to an island-shaped region of the shield electrode SL1 whichis surrounded by four openings OP1. Therefore, the electrode portionsIE1 have, for example, a substantially square shape.

In the example illustrated, regarding each opening OP1 located on thewiring line WLa side, the entire region overlaps the power line VP1. Onthe other hand, regarding each opening OP1 located on the wiring lineWLb side, substantially half of the region overlaps the power line VP1.In the present embodiment, the total area (first area) of regions inwhich the openings OP1 and the power line VP1 overlap is greater than orequal to 20% of the area (second area) of a region in which the powerline VP1 and the shield electrode SL1 overlap. The second area herecorresponds to the sum of the total area (first area) of the openingsOP1 overlapping the power line VP1 and the total area of the electrodeportions IE1 overlapping the power line VP1, of the shield electrodeSL1. In addition, the first area should preferably be greater than orequal to 30% and less than or equal to 70% of the second area.

Furthermore, in a case where the area of the shield electrode SL1 is thesum of the total area of the openings OP1 and the total area of theelectrode portions IE1, the total area of the openings OP1 is greaterthan or equal to 20% of the area of the shield electrode SL1, morepreferably, greater than or equal to 30% and less than or equal to 70%of the area of the shield electrode SL1.

FIG. 11 is an enlarged plan view of a part of the shield electrode SL1shown in FIG. 10. FIG. 11 is a plan view in an a-b plane defined by adirection a and a direction b. The direction a and the direction b areorthogonal to each other and correspond to directions in which the sidesof the opening OP1 which are orthogonal to each other extend. In thepresent embodiment, the openings OP11 and OP12 have substantially thesame size. That is, a length a1 of the sides extending in the directiona of the opening OP11 and a length a2 of the sides extending in thedirection a of the opening OP12 are equal. In addition, a length b1 ofthe sides extending in the direction b of the opening OP11 and a lengthb2 of the sides extending in the direction b of the opening OP12 areequal. The size of the opening OP11 and the size of the opening OP12 canbe appropriately changed in accordance with the frequency of EMI noiseto be blocked. The lengths a1, b1, a2 and b2 are, for example, greaterthan or equal to 10 μm and less than or equal to 500 μm.

FIG. 12 is an enlarged plan view of a region A2 shown in FIG. 6. Theregion A2 is a region including the end portion EX2 and the end portionEY2. The power line VP2 provided in the first substrate SUB1 is locatedbetween the display region DA and the end portion EY2 and extends in adirection in which the drive electrodes Tx are arranged, that is, in thesecond direction Y.

The shield electrode SL2 is provided along the end portions EX2 and EY2.The shield electrode SL2 is, for example, spaced apart from both the endportion EX2 and the end portion EY2. The shield electrode SL2 overlapsthe power line VP2. In the example illustrated, a width WY2 of theshield electrode SL2 extending along the end portion EY2 is greater thana width WX2 of the shield electrode SL2 extending along the end portionEX2.

In the example illustrated, the second substrate SUB2 comprises a shieldelectrode SL4 arranged between the shield electrode SL2 and thedetection electrodes Rx. The potential of the shield electrode SL4 is,for example, the same potential as that of the detection electrode Rx.Alternatively, the potential of the shield electrode SL4 may be, forexample, a fixed potential such as a ground potential. The shieldelectrode SL4 is located in the display region DA, and as is the casewith the detection electrode Rx, the shield electrode SL4 is formed ofwavy thin metal wires. Note that the shield electrode SL4 may beomitted.

FIG. 13 is an enlarged plan view of the vicinity of the power line VP2shown in FIG. 12. The shield electrode SL2 comprises openings OP2 andelectrode portions IE2. A part of the shield electrode SL2 overlaps thepower line VP2 in a planar view. That is, at least some of the openingsOP2, and some of the electrode portions IE2 overlap the power line VP2.The openings OP2 are regularly arranged. In the example illustrated, theopenings OP2 are arranged in the first direction X and the seconddirection Y. In addition, the openings OP2 are arranged in a staggeredmanner in directions in which thin wires TW21 and TW22 which form theopenings OP2 extend. The openings OP2 have, for example, a substantiallysquare shape. Each electrode portion IE2 corresponds to an island-shapedregion of the shield electrode SL2 which is surrounded by four openingsOP2. Therefore, the electrode portions IE2 have, for example, asubstantially square shape.

In the present embodiment, the total area (third area) of regions inwhich the openings OP2 and the power line VP2 overlap is greater than orequal to 20% of the area (fourth area) of a region in which the powerline VP2 and the shield electrode SL2 overlap. The fourth area herecorresponds to the sum of the total area (third area) of the openingsOP2 overlapping the power line VP2 and the total area of the electrodeportions IE2 overlapping the power line VP2, of the shield electrodeSL2. In addition, the third area should preferably be greater than orequal to 30% and less than or equal to 70% of the fourth area.

FIG. 14 is an illustration for explaining the relationship between thetotal area of the openings OP1 and the shielding effect of the shieldelectrode SL1, and the shape of the overcoat layer OC. The shieldelectrode SL1 of the present embodiment is shown in (b) of FIG. 14. Ashield electrode ES1 and a shield electrode ES2 as comparative examplesare shown in (a) of FIG. 14 and (c) of FIG. 14, respectively. The shieldelectrodes SL1, ES1 and ES2 are formed on the basement 20 and arecovered with the overcoat layer OC.

As shown in (a) of FIG. 14, the total area of openings EO1 provided inthe shield electrode ES1 is greater than the total area of the openingsOP1 provided in the shield electrode SL1 shown in (b) of FIG. 14. In theexample illustrated, the openings EO1 and the openings OP1 have the samesize, and the number of the openings EO1 is substantially twice thenumber of the openings OP1. According to the shield electrode ES1 havingsuch a structure, when the overcoat layer OC is applied, the overcoatlayer OC is held in the shield electrode ES1. On the other hand, sincethe total area of the openings EO1 is large, the shielding performanceagainst EMI noise radiating from the power line VP1 will be deterioratedin a case where the power line VP1 is located below the shield electrodeES1.

As shown in (c) of FIG. 14, the shield electrode ES2 does not haveopenings. Therefore, most of EMI noise radiating from the power line VP1can be blocked. On the other hand, according to the shield electrode ES2having such a structure, when the overcoat layer OC is applied, theovercoat layer OC tends to spread on the shield electrode ES2.Therefore, the thickness of the overcoat layer OC tends to become lessthan a desired thickness.

On the other hand, as shown in (b) of FIG. 14, according to the presentembodiment, the first area in which the openings OP1 and the power lineVP1 overlap is set to be greater than or equal to 20%, more preferably,greater than or equal to 30% of the second area in which the openingsOP1 and the electrode portions IE1 of the shield electrode SL1 overlapthe power line VP1. As a result, the contact area in which the overcoatlayer OC and the basement 20 are in contact with each other can besecured, and the spreading of the overcoat layer OC can be suppressed.In addition, the first area is set to be less than or equal to 70% ofthe second region. As a result, the shielding performance against theEMI noise radiating from the power line VP1 can be sufficientlyobtained. In the case of the shield electrode SL2 shown in FIG. 13 also,similar advantageous effects can be obtained.

That is, according to the present embodiment, the shield electrode SL1having the openings OP1 and the electrode portions IE1 is provided inthe region overlapping the power line VP1, and the shield electrode SL2having the openings OP2 and the electrode portions IE2 is provided inthe region overlapping the power line VP2. Therefore, the overcoat layerOC which is to be provided on the shield electrodes SL1 and SL2 can beformed with a desired thickness, and the EMI noise radiating from thepower lines VP1 and VP2 can be blocked. As a result, the highly-reliabledisplay device 1 can be provided.

In addition, the openings OP1 and OP2 are regularly arranged. Therefore,the shielding performance against the EMI noise radiating from the powerlines VP1 and VP2 can be uniformly obtained in both the region in whichthe power line VP1 and the shield electrode SL1 overlap and the regionin which the power line VP2 and the shield electrode SL2 overlap.

Furthermore, since the shield electrode SL2 has the electrode portionsEI2, the resistance value of the shield electrode SL2 is reduced. As aresult, radiation of ESD noise via the shield electrode SL2 issuppressed, and damage of the sensor 4 can be reduced.

FIG. 15 is a plan view showing another example of the shield electrodeSL1. The example shown in FIG. 15 is different from the example shown inFIG. 11 in that the size of the opening OP11 is different from the sizeof the opening OP12. In the example illustrated, the length a1 isgreater than the length a2, and the length b1 is greater than the lengthb2. In the present example also, advantageous effects similar to thoseof the example shown in FIG. 11 can be obtained. In addition, accordingto the present example, a distance Da in the direction a between theopening OP11 and the opening OP12 is greater than a distance Da in thedirection a between the opening OP11 and the opening OP12 in FIG. 11.Furthermore, a distance Db in the direction b between the opening OP11and the opening OP12 is greater than a distance Db in the direction bbetween the opening OP11 and the opening OP12 in FIG. 11. Therefore, theresistance value of the shield electrode SL1 can be reduced. Inaddition, even if leakage of EMI noise from the opening OP11 occurs,leakage of EMI noise of the same frequency from the opening OP12 can besuppressed, and the shielding performance can be improved.

FIG. 16 is a plan view showing another example of the shield electrodeSL1. The example shown in FIG. 16 is different from the example shown inFIG. 15 in that the opening OP11 has a substantially rectangular shape.In the example illustrated, the length a1 is greater than the length a2,and the length b1 is substantially equal to the length b2. In thepresent example also, advantageous effects similar to those of theexample shown in FIG. 15 can be obtained.

Note that the examples shown in FIGS. 15 and 16 can also be applied tothe shield electrode SL2.

In the above-described embodiment, the shield electrode SL1 correspondsto the first shield electrode. The openings OP1 and OP11 correspond tothe first opening, and the electrode portion IE1 corresponds to thefirst electrode portion. The power line VP1 corresponds to the firstpower line. The shield electrode SL2 corresponds to the second shieldelectrode. The opening OP2 corresponds to the second opening, and theelectrode portion IE2 corresponds to the second electrode portion. Inaddition, the opening OP12 corresponds to the third opening. The shieldelectrode SL3 corresponds to the third shield electrode. The overcoatlayer OC corresponds to an organic insulating layer.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the inventions. Indeed, the novel embodiments described hereinmay be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the embodimentsdescribed herein may be made without departing from the spirit of theinventions. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the inventions.

What is claimed is:
 1. A display device comprising: a plurality of driveelectrodes; a mesh-patterned first shield electrode comprising aplurality of first openings and a first electrode portion locatedbetween the first openings adjacent to each other, an area of the firstelectrode portion being greater than an area of the first openings; anda first power line provided with a predetermined voltage, wherein thefirst openings and the first electrode portion overlap the first powerline.
 2. The display device according to claim 1, wherein the firstpower line is provided with an AC voltage.
 3. The display deviceaccording to claim 1, wherein a first area in which the first power lineand the first opening overlap is greater than or equal to 20% of asecond area in which the first power line and the first shield electrodeoverlap.
 4. The display device according to claim 3, wherein the firstarea is greater than or equal to 30% and less than or equal to 70% ofthe second area.
 5. The display device according to claim 1, furthercomprising a first substrate comprising drive electrodes; a secondsubstrate facing the first substrate and comprising detectionelectrodes; and a mesh-patterned second shield electrode arranged on anoutside of the first shield electrode in the second substrate, whereinthe second shield electrode comprises a second opening and anisland-shaped second electrode portion.
 6. The display device accordingto claim 5, further comprising a second power line provided in the firstsubstrate and electrically connected to the drive electrodes, whereinthe second power line extends in a direction in which the driveelectrodes are arranged, and the second opening and the second electrodeportion overlap the second power line.
 7. The display device accordingto claim 6, wherein a third area in which the second power line and thesecond opening overlap is greater than or equal to 20% of a fourth areain which the second power line and the second shield electrode overlap.8. The display device according to claim 7, wherein the third area isgreater than or equal to 30% and less than or equal to 70% of the fourtharea.
 9. The display device according to claim 1, wherein the firstshield electrode comprises a third opening spaced apart from the firstopening, and a size of the first opening and a size of the third openingare different from each other.
 10. The display device according to claim5, further comprising: wiring lines provided in the second substrate andelectrically connected to the detection electrodes; and a third shieldelectrode provided in the second substrate and located between thewiring lines and the detection electrodes.
 11. The display deviceaccording to claim 5, wherein a potential of the first shield electrodeis a potential equal to either a fixed potential or a potential of thedetection electrodes.
 12. The display device according to claim 5,wherein the second substrate has a first surface facing the firstsubstrate and a second surface located on an opposite side from thefirst surface, and the first shield electrode and the detectionelectrodes are located on the second surface, and are formed of a samematerial.
 13. The display device according to claim 12, furthercomprising an organic insulating layer covering the first shieldelectrode and the detection electrodes.
 14. A touch detection devicecomprising: a plurality of drive electrodes; a plurality of detectionelectrodes; a mesh-patterned first shield electrode comprising aplurality of first openings and a first electrode portion locatedbetween the first openings adjacent to each other, an area of the firstelectrode portion being greater than an area of the first openings; anda first power line provided with a predetermined voltage, wherein thefirst openings and the first electrode portion overlap the first powerline.
 15. The touch detection device according to claim 14, wherein afirst area of the first opening of the first shield electrode is greaterthan or equal to 20% of an area of the first shield electrode.
 16. Thetouch detection device according to claim 15, wherein the first area isgreater than or equal to 30% and less than or equal to 70% of the areaof the first shield electrode.
 17. The touch detection device accordingto claim 14, wherein the first shield electrode comprises a thirdopening spaced apart from the first opening, and a size of the firstopening and a size of the third opening are different from each other.18. The touch detection device according to claim 14, furthercomprising: wiring lines electrically connected to the detectionelectrodes; and a third shield electrode located between the wiringlines and the detection electrodes.
 19. The touch detection deviceaccording to claim 14, wherein a potential of the first shield electrodeis a potential equal to either a fixed potential or a potential of thedetection electrodes.
 20. A touch detection device comprising: aplurality of drive electrodes; a plurality of detection electrodes; amesh-patterned first shield electrode comprising a plurality of firstopenings and a first electrode portion located between the firstopenings adjacent to each other, an area of the first electrode portionbeing greater than an area of the first openings; a first power lineprovided with a predetermined voltage, the first power line overlappingthe first opening and the first electrode portion; and a mesh-patternedsecond shield electrode arranged on an outside of the first shieldelectrode, the second shield electrode comprising a second opening andan island-shaped second electrode portion.